Friction welding is a joining process that, unlike traditional welding methods, can be used to join non-identical alloys. Rotary friction welding has become increasingly attractive for many sectors due to its advantages like cost, economy, weight minimization and unique features, as well as the sustainable advantages it offers. However, the formation and existence of brittle intermetallic compounds (IMCs) at the weld interface can create difficulty in the welding process of aluminum-aluminum and aluminum-steel alloys. In this study, the welding properties as well as the temperature and tensile strengths of two 20 mm diameter aluminum 6061 series shafts produced by rotary friction welding were examined. The adhesion properties of shafts with different surface properties that may occur at the interface are discussed. In addition to examining the effect of heat input and different surface properties on heat generation, the adhesion properties of shafts with different surface roughness were examined by tensile tests in accordance with the ASTM D790 standard.